Aspects of the disclosure relate to augmented reality. More specifically, aspects of the disclosure relate to radiance transfer sampling for augmented reality.
Photorealistic rendering of combined virtual and real scenes is a fundamental goal for many augmented reality (AR) applications, such as games or advertising. Current solutions make use of existing software development kits to obtain scene models with real time updates and 3-D tracking of the camera used to capture the image. A solution aiming at photorealistic AR images based on global illumination will typically compute the radiance transfer (RT) for every surface point in view. The RT is used to sample environment illumination information directly from the scene model. The RT information together with the environment illumination and the scene model is used to generate realistic renders of virtual objects in the real scene. The resulting images have a perceptually plausible approximation of the light interactions between the environment, virtual objects, and real objects.
However, computing RT for dynamically changing scenes represented as voxel volumes requires volumetric raytracing. Applying this procedure for all visible surface points of the scene model in every frame is computationally expensive. Even with the use of faster processors, it is likely necessary to resort to regular subsampling to obtain acceptable interactive speeds. The use of simple subsampling introduces undesirable aliasing artifacts and is not an optimal solution.